Metal venom in dental amalgam

After doing a filling work on a patient’s teeth, dentists often guarantee that the material used will last as long as the patient lives. They can say this with conviction because the material used in the filling comprise mostly of mercury. Patients also often boast about how good their dentists are and how wonderfully long lasting the fillings have been. But very few of them have the idea that the longer the mercury resides in their bodies, the greater are the chances of catching the likes of skin cancer, kidney and brain damage, weakened immunity, memory loss and reproductive complication, and other deadly diseases. A study conducted by the Environment and Social Development Organisation has found that a vast majority of nearly 85% people in Bangladesh are not aware of the impact that mercury-heavy dental amalgam can have on human health and environment. The mercury that the people in Bangladesh are exposed to is hundreds of times higher than international safety limits, because most dentists here use amalgam, to save costs, the Dhaka Tribune has found. Amalgam is a mixture, half of which is made up of mercury and other half of heavy metals such as silver, tin, zinc and copper. Because it is known as the cheapest solution for dental cavity, not surprisingly amalgam is the most widely used filling, especially in low-income countries like Bangladesh. The silver-coloured amalgam, used for filling up cavities caused by tooth decay, has been in use for more than 150 years around the world, making it one of the oldest materials used in oral health care. Alarmingly, mercury is also one of the ten chemicals of major public health concern that WHO prioritises. According to private practitioner Dr Altamash Mahmood, depending on the size, a tooth cavity may need up to 5mg of amalgam which can contain up to 2.5mg of mercury. Dentists charge from Tk200 to Tk500 for filling up one unit of cavity using the dental amalgam, he said. Dr Mohidus Samad Khan, assistant professor of chemical engineering at the Bangladesh University of Engineering and Technology (Buet), said there are two different global chemical safety standards: one maintained by the Food and Agriculture Organisation (FAO) of the UN and the WHO, and the other by the US Environmental Protection Agency (EPA). According to FAO and WHO, an adult weighing around 70kg can safely tolerate up to 112 microgram (μgm) of mercury every day. The US EPA maintains that an adult of similar weight can tolerate up to 7μgm of mercury every day, he said. Considering that 1mg equals 1,000μgm, a standard one-tooth filling therefore contains up to 2,500μgm of mercury, which is more than 22 times higher than the FAO/WHO daily limit and a staggering 357 times than the US EPA limits. These figures, which already appear alarming, actually refer to daily exposures. Therefore, a standard tooth filling will continue to cause slow poisoning for as long as it stays inside the human body which may even be decades. In […]